ReFS, Microsoft's next generation file system revealed

Microsoft detailed its long awaited and arguably well overdue NTFS replacement yesterday, the Resilient File System (ReFS), on the Building Windows 8 blog. It marks the first time the Redmond-based software giant has revealed the specifics of its next-gen file system in full.

The company claims ReFS has been built from the ground up, to meet the demands of the storage requirements needed by Windows users. It offers the ability to handle large storage volumes, enhanced resiliency to corruption and shared storage pools across multiple machines.

"ReFS inherits the features and semantics from NTFS including BitLocker encryption, access-control lists for security, USN journal, change notifications, symbolic links, junction points, mount points, reparse points, volume snapshots, file IDs, and oplocks," Surendra Verma, the development manager for the Storage and File System team wrote.

It will only be available for Windows Server 8 products initially, with Microsoft stating it plans to fully test the file system before offering it on other Windows 8 products in the future. So despite the advantages it offers, those adopting Windows 8 from the outset will have to remain with the very outdated NTFS file system.

Also, in its current state ReFS cannot be used for removable media, or for any partition used to boot Windows – it is purely a file system solution for data storage right now. Windows 8 clients will be able to access and read ReFS partitions from launch though.

Essentially it just plugs into the existing NTFS storage stack and has been built upon the foundations of its predecessor, in order to maintain compatibility. Its main benefits include being able to detect and automatically correct storage corruption whilst keeping the disk online during repairs, and data striping support similar to RAID solutions without the added complexity that would normally create for users.

ReFS will also incorporate Microsoft’s write model, Copy-on-Write (COW), which the firm has used with great success in its SQL server products and Volume Shadow Copy Service that enables users to make quick snapshots of large datasets.